Previously, many types of heating systems have been used in endeavoring to provide an effective means to heat liquids within a pipe or chamber.
A search of the prior art did not disclose any patents that possess the novelty of the instant invention; however the following U.S. patents are considered related:
U.S. Pat. No.InventorIssue Date3,378,673HopperApr. 16, 19683,716,693BleckmannFeb. 13, 19735,408,579HuntApr. 18, 19955,497,824RoufMar. 12, 19965,774,627JacksonJun. 30, 19986,078,730Huddart et al.Jun. 20, 20006,539,171 B2VonArx et al.Mar. 25, 2003
Bleckmann in U.S. Pat. No. 3,716,693 discloses an electrical tubular heating element consisting of a metal outer tube with heating resistance arranged in the outer tube. The zone adjacent to the inner wall of the tube is filled with an insulating material with a high melting point. Adjacent to the heating resistance is a layer of glass such that when the outer tube temperature reaches a predetermined value the leakage current switches off the heating element.
U.S. Pat. No. 5,408,579 issued to Hunt is for an electric heating assembly having a resistance heating wire disposed within a metal sheath. A sleeve or liner extends into the sheath sufficiently to surround a heated portion of the wire adjacent to the inner end of its respective pin.
Rouf in U.S. Pat. No. 5,497,824 teaches discloses heat transfer method having fluid passing through a turbulator and a helical coil inside or outside of a tube. The turbulator includes a twisted strip surrounded by a helical coil that is closely spaced from the walls of the tube. Heat transfer to a second fluid is accomplished through the use of a helical coil installed on the outside of the tube.
U.S. Pat. No. 5,774,627 issued to Jackson discloses a heating element for a water heater with a resistance wire coiled within a heat conducting material such as magnesium oxide powder. The number of coil returns per unit lengthen of element in bend areas may be reduced by stretching the coiled heating wire to attain the desired length of resistance wire per unit length of the element. Reduced power at the bend lowers element temperature reducing water scaling and extending the life of the element.
Huddart et al. in U.S. Pat. No. 6,078,730 discloses a heated corrugated conduit with a heater wire within the conduit. The heater wire is a spirally wound helix having a varying pitch providing different levels of heat within the conduit.
U.S. Pat. No. 6,539,171 B2 of VonArx et al. teaches heating elements that are spirally shaped in a plurality of forms which are thermally conductive and electrically insulated with a polymeric coating such as a fluorocarbon resinous material.
For background purposes and as indicative of the art to which the invention is related reference may be made to the remaining cited patent issued to Hooper in U.S. Pat. No. 3,378,673.